Article Index

Page 4 of 14

Page 54

#define _GNU_SOURCE
#include <gpiod.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
int res;
int main(int argc, char **argv) {
    for (;;) {
         res = gpiod_ctxless_set_value("0", 4, 1, 1,  "output test", NULL, NULL);
         res = gpiod_ctxless_set_value("0", 4, 0, 1,  "output test", NULL, NULL);
    }
}
 

 Remember to change "0" to "4" if running on a Pi 5.

Page 55 

#define _DEFAULT_SOURCE
#include <gpiod.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
int res;

int delayms(int ms)
{
    struct timespec delay = {0, ms * 1000 * 1000};
    return nanosleep(&delay, NULL);
}

int main(int argc, char **argv)
{

    for (;;)
    {
        res = gpiod_ctxless_set_value("0", 4, 1, 1, "output test", (gpiod_ctxless_set_value_cb)delayms, (void *)100);
        res = gpiod_ctxless_set_value("0", 4, 0, 1, "output test", (gpiod_ctxless_set_value_cb)delayms, (void *)100);
    }
}

 Remember to change "0" to "4" if running on a Pi 5.

Page 56 

#define _DEFAULT_SOURCE
#include <gpiod.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>
int res;
int delayms(int ms)
{
    struct timespec delay = {0, ms * 1000 * 1000};
    return nanosleep(&delay, NULL);
}
int main(int argc, char **argv)
{
    int offsets[] = {4, 17};
    int state1[] = {1, 0};
    int state2[] = {0, 1};
    for (;;)
    {
        gpiod_ctxless_set_value_multiple("0", offsets, state1, 2, 1, "output test", (gpiod_ctxless_set_value_cb)delayms, (void *)1);
        gpiod_ctxless_set_value_multiple("0", offsets, state2, 2, 1, "output test", (gpiod_ctxless_set_value_cb)delayms, (void *)2);
    }
}
 
 Remember to change "0" to "4" if running on a Pi 5.

Page 58

#define _GNU_SOURCE
#include <gpiod.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
    int res;
    struct gpiod_chip *chip = gpiod_chip_open_by_number(0);
    const char *name = gpiod_chip_name(chip);
    int num = gpiod_chip_num_lines(chip);
    printf("%s %d", name, num);
    gpiod_chip_close(chip);
} 

 Remember to change chip number 0 to 4 if running on a Pi 5.

Page 60 

#define _GNU_SOURCE
#include <gpiod.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
    int res;
    struct gpiod_chip *chip = gpiod_chip_open_by_number(0);
    struct gpiod_line *line4 = gpiod_chip_get_line(chip, 4);
    res = gpiod_line_request_output(line4, "test output", 0);

    for (;;)
    {
        res = gpiod_line_set_value(line4, 1);
        res = gpiod_line_set_value(line4, 0);
    };
} 

 Remember to change chip number 0 to 4 if running on a Pi 5.

 

Page 64

#define _GNU_SOURCE
#include <gpiod.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

int main(int argc, char **argv)
{
    int res;
    struct gpiod_chip *chip = gpiod_chip_open_by_number(0);
    struct gpiod_line_bulk bulk;
    gpiod_line_bulk_init(&bulk);
    gpiod_line_bulk_add(&bulk, gpiod_chip_get_line(chip, 4));
    gpiod_line_bulk_add(&bulk, gpiod_chip_get_line(chip, 17));

    res = gpiod_line_request_bulk_output(&bulk, "test", 0);
    for (;;)
    {
        gpiod_line_set_value_bulk(&bulk, (int[2]){0, 1});
        gpiod_line_set_value_bulk(&bulk, (int[2]){1, 0});
    };
}
 

 Remember to change chip number 0 to 4 if running on a Pi 5.

 

Page 66 

#define _GNU_SOURCE
#include <gpiod.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <time.h>

void gpiod_line_release(struct gpiod_line *line);

int main(int argc, char **argv)
{
    int res;
    struct timespec delay = {0, 10 * 1000 * 1000};
    struct timespec time1, time2;

    struct gpiod_chip *chip = gpiod_chip_open_by_number(0);
    struct gpiod_line *line4 = gpiod_chip_get_line(chip, 4);

    res = gpiod_line_request_input(line4, "RMeasure");
    nanosleep(&delay, NULL);
    gpiod_line_release(line4);

    res = gpiod_line_request_output(line4, "RMeasure", 0);
    nanosleep(&delay, NULL);
    gpiod_line_release(line4);

    clock_gettime(CLOCK_REALTIME, &time1);
    gpiod_line_request_input(line4, "RMeasure");
    while (gpiod_line_get_value(line4) == 0)
    {
    };
    clock_gettime(CLOCK_REALTIME, &time2);
    printf("Time=%d", (time2.tv_nsec - time1.tv_nsec) / 1000);
}  
 

 Remember to change chip number 0 to 4 if running on a Pi 5.